Thread cutter and clamp for sewing-machines.



v F.ZALESKI. THREAD CUTTER AND CLAMP FOR SEWING MACHINES. APPLICATION FILED MAY 22, 1915.

1,197,887. Patented Sept. 12, 1916.

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FRANKZALESKL- 0F SOMER' J'ILLE, MASSACHUSETTS, ASSIGNOR TO THE BEEGE BUTTON HOLE MACHINE GOM TBANY, OF BOSTON, MASSACHUSETTS, A CORPORA- TION OF MAINE.

THREAD CUTTER AND CLAMP non snwme-rmonmns.

Specification of Letters Patent.

Patented Sept. 12,1916.

Application filed May 22, 1915. Serial No. 29,900.

To all whom it may concern: 7

Be it known that I, FRANK- ZALESKI, a subject of the Emperor of Germany, residing at Somerville, county of Middlesex, State of Massachusetts, have invented an Improvement in Thread Cutters and Clamps for Sewing-Machines, of which the following description, in connection with the accompanying drawing, is a specification, like characters on the drawing representing like parts.

This invention has for its object to provide a novel thread clamping and cutting device adapted for use in connection with a buttonhole sewing machine and which operates automatically to cut the needle thread and hold the-end thereof leading to the source of supply at the end ofthe stitch-.

ing operation on a buttonhole, said device retaining its hold on the needle thread until after the initial stitches have been formed on the next buttonhole.

lVhile my invention is capable of use in connection with buttonhole sewing machines of various types, I have chosen herein to illustrate it as it would be embodied in a buttonhole sewing machine of the so-called Reece type, examples of which may be found in the following United States Letters Patent: No. 494,280, dated March 28, 1893; No. 655,637, dated August 7, 1900; No. 1,019,693, dated March 12, 1912.

The sewing machines illustrated in the above-mentioned patents include in their construction a clamp frame having work clamps secured thereto and a so-called stitchposition, after which the stitch frame and clamp frame have a relative movement to bring the stitch-forming lnstrumentallties into proper POSltlOIItO stitch the button hole. The stitch-forming mechanism is then automatically set in operation and the stitch frame and clamp frame have a further feeding movement to carry the stitches down one side of the buttonhole, around the eye thereof'and back the other side of the buttonhole. lVhen the stitching on the buttonhole is completed, the stitch-forming mechanism is brought to rest automatically and the clamp frame and stitch frame have a further relative; movement to bring the parts to their initial position,- the Work clamp being automatically released at the end'of the stitching operation. 7

My present invention involves a novel thread-clamping and cutting device which is carried by the work clamp and is operated by the relative movements of the two frames to cut the needle thread between the needle and the work at the end of the stitching operation, and to" hold the severed end of the needle thread until the stitching operation has begun on the next buttonhole.

In order to give an understanding ofmy invention I have illustrated in the drawings a selected embodiment thereof which will now be described, after which the novel features will be pointed out in the appended claims.

In the drawings, Figure 1 is a side view of a portion ofa buttonhole sewing machine of the Reece type having myimprovements applied thereto; Fig. 2 is a plan view of a portion of the work clamp showing my improved thread-clamping and the position they assume at the beginning of the stitching operation; Fig. 4 is a similar view showing the position of the parts after the initial stitches have been formed on the buttonhole; Fig. 5' is an underside viewof the combined cutter and clamp; Fig. 6 is an enlarged section on the line a&, Fig. 3. Fig. 7 is a transversesection through the cutter and clamp.

In the drawings 1 designates the so-called clamp frame of-the sewing machine which is provided with the work clamps 2 carried by arms 3 pivoted to the clamp frame at d, as usual in sewing machines of this-type. 5 is a portion'of the so-called stitch frame which carries the upper and under thread mechanism, said stitch frame being constructed to provide the usual overhanging arm 6 in which reciprocates the needle bar 7 that carries the needle 8 of the upper thread mechanism. In buttonhole sewing machines of this type the needle bar not only reciprocates but also has a rotary movement to effect the stitching around the ends of the buttonhole, this being provided for by a gear 11 by which the needle bar may be turned, which gear meshes with a sector 12 carried by a shaft 9 that is operated to effect the desired rotation of the needle bar. The parts of the under thread mechanism are not illustrated herein, as they are not nec essary to an understanding of the invention.

In the operation of a sewing machine of this type, the stitch frame and clamp frame have the relative positions shown in full lines at the end of the stitching operation. hen the machine is set in operation the work clamps 2 will be automatically depressed against the work thereby clamping the latter in position, and the stitch frame 5 moves to the right, Fig. 1, into the dotted line position, thereby bringing the stitchforming mechanism into proper position to stitch the buttonhole. The stitching operation then begins and the stitch frame has a further movement to carry the stitching down one side of the buttonhole and around the end thereof and up the other side, and when the stitch frame again reaches substantially the dotted line position, Fig. 1, the stitching on the buttonhole is completed and the stitching mechanism is brought to rest. The work clamps are then released and the stitch frame is moved forwardly into the full line position Fig. 1, thus restoring the parts to their initial position.

My improved thread cutter and clamp is of that type which is secured to the workclamping means and is provided with an open throat so situated that when the needle moves from the dotted to the full line position Fig. 1 at the end of the stitching operation the needle thread 2? will be drawn into said open throat and the thread-cutting and clamping mechanism will be operated by the relative movement of the stitch frame and clamp frame to cut the needle thread and hold the end thereof.

My improved thread clamp and cutter comprises a circular housing or holder 13 which is secured to the end of an arm 14: that in turn is fastened to the arm 3 carrying the work clamp. This holder 13 is provided with the open slot 15 extending inwardly from one edge thereof and so situated that when the stitch frame moves from the dotted to the full line position, Fig. 1, the needle thread 2? will be carried into said slot. This housing or holder 13 incloses a thread cutter and thread-clamping element 16 which is circular in shape and is centrally pivoted within the housing on the stud 17. This cutter is provided with a slot or notch 18 which in one position of the cutter is alined with the slot 15 in the housing. One edge 19 of the slot 18 is shaped to constitute a cutting edge which cooperates with the edge 20 of the slot 15 at the bottom of the holder 13 to cut or shear the thread as the cutter turns about its axis. The end of the thread leading to the needle is clamped at the time that the thread is cut by being drawn in between the upper edge or corner 21 of the slot 18 and the edge 22 of the housing or holder.

The thread-cutting and clamping move-' ment of the cutter element 16 is secured from the relative movement of the stitch frame and clamp frame when the stitch frame moves from the dotted to the full line position Fig. 1, and while any suitable means for accomplishing this may be employed, I have herein shown an actuating member 23 in the form of a finger which is secured to the stitch frame at at and is provided with two opposed shoulders 25 and 26 that cooperate with a pin or projection 27 rising from an arm 28 that extends from the cutter 16 and passes through a slot 29 in the housing. The pin 27 stands normally between the shoulders 25 and 26 and in the position shown in Fig. 2 when the stitch frame and clamp frame are in the relative positions shown in full lines Fig. 1. WVhen the stitch frame moves into the dotted line position, Fig. 1, the shoulder 26 engages the pin 27 and turns the cutter element to bring the slot 18 therein in alinement with the slot 15 in the housing. As the stitch frame has a further feeding movement during the formation of the stitches down one side of the buttonhole, the shoulder 26 is carried past the pin 27 as seen in Fig. 4, this being permitted by the resiliency of the actuating member 23. When the stitching on the buttonhole is completed the actuating memline position shown in Fig. 2 and cutting the needle thread and clamping the latter, as shown in Fig. 6. The clamp and cutter are preferably constructed so that they will have sufficient frictional engagement with the housing to hold them in any position in which they may be placed, and, therefore, when the parts are in the position shown in Fig. 3, the end of the needle thread will be clamped by the device and will be held clamped until the cutter is moved into the position shown in Fig. 4. This turning movement of the member 16 to unclamp the thread occurs during the formation of the initial stitches on the buttonhole, for the shoulder 26 is so positioned that when the stitch frame has assumed: the dotted line position Fig. 1, which is the position it occupies at the beginning of the stitchingop eration, the shoulder 26 will be brought against the pin 27, as'shown in Fig. 3. During the formation-ofthe first stitches of the buttonhole, the stitch frame will move farther to the right, Fig. 1, than the dotted line position, and during this movement the shoulder 26 will act 'against'the pin-27 to move the element 16' into a position to release the thread. The-thread 25 will, however,

be held in the clamp until after the first few stitches have been formed.

I have herein shown the shoulder 26 as formed on a block 35 which is adjustably secured to the end of the arm 23 by means of screws '37 extending through slots 36 in the block 35-. The advantage of this construction is that the block 35 can be adjusted so as to position the shoulder 26 nearer to or farther from the shoulder 25.

While I have illustrated herein one embodiment of my invention I do not wish to be limited to the constructional features shown.

I claim:

1. In a sewing machine, the combination with work-clamping means, of stitch-forming mechanism including a needle, said work-clamping means and stitch-forming mechanism having a movement relative to each other after the needle has been brought to rest upon the completion of a predetermined stitching operation, a thread-cutting device secured to the work-clamping means and comprising a relatively-fixed member, a cutting element pivotally connected to said relatively-fixed member and cotiperating therewith to cut the needle thread, and means to actuate said pivoted member by such relative movement of the stitch-forming mechanism and work-clamping means.

2. In a sewing machine, the combination with work-clamping means, of stitch-forming mechanism including a needle, said Work-clamping means and stitch-forming mechanism having a movement relative to each other after the needle has been brought to rest upon the completion of a predetermined stitching operation, a thread-cutting device carried by the work-clamping means and comprising a relatively-fixed member having a thread-receiving throat situated so that the needle thread is drawn into the throat during such relative movement of the stitch-forming mechanism and work-clamping means, a cutting element pivotally connected to the fixed member and cooperating therewith to cut the thread, and means to actuate said pivoted member by said relative movement between the stitch-forming mechanism and work-clamping means.

3. In a sewing machine, the combination with a clamp-frame, of a stitch frame carrying needle-actuating means, said frames having a movement relative to each other, a needle-thread-cutting device comprising a circular housing having a thread-receiving slot, a circular cutting element centrally pivoted within-the housing and provided With a slot which is movable into and out of alinement with the slot in the housing, and means to actuate said cutting element by said relative movement of the frames.

4. In-a sewing machine, the combination with a clamp frame carrying work-clamping means, of a stitch frame carrying needle-actuating means, said frames having a movement relative to each other, a needle-threadcutting device comprising a circular housing secured to the work-clamping means and provided with a thread-receiving slot situated so that the needle thread will be drawn into said slot by said relative movement of the'frames at the end of the stitching operation, a circular cutting element centrally pivoted within the housing, and means to actuate said cutting element to cut the thread by said relative movement of the frames.

5. In a sewing machine, the combination with work-clamping means situated above the work, of stitch-forming mechanism including a needle, said work-clamping means and stitch-forming mechanism having a movement relative to each other, a threadcutting device secured to the work-clamping means, and comprising a circular housing having a thread-receiving slot, a circular cutting element centrally pivoted within the housing and provided with a slot which is movable into and out of alinement with the slot in the housing, and means to actuate said cutting element by said relative movement of the stitch-forming mechanism and work-clamping means.

6. In a sewing machine, the combination with a frame carrying stitch-forming mechanism including a needle, of work-clamping means, said frame and work-clamping means having a movement relative to each other after the needle has been brought to rest upon the completion of a predetermined stitching operation, a thread cutter carried by the work-clamping means and compris-' ing a relatively-stationary member having a thread-receiving slot situated so that the needle thread is drawn into the slot during such relative movement of the frame and work-clamping means, a thread-cutting element pivoted to said fixed member and pro vided with an arm, and an actuating member secured to the frame and cotiperating with said arm to actuate the thread cutter during such relative movement.

7. In a sewing machine, the combination with work-clamping means, of stitch-forming mechanism in luding a needle, said work clamping means and stitch forming mechanism having a movement relative to each other after the needle has been brought to rest at the end of a predetermined stitching operation, a thread cutter and clamp carried by the work-clamping means and comprising a relatively-fixed member, a thread-cutting and clamping member pivotally connected to the relatively-fixed memher, and means to actuate said pivoted member by such relative movement of the frame to cut the needle thread and clamp the latter.

8. In a buttonhole sewing machine, the combination with stitch-forming mechanism, of work-clamping means, said stitchforming mechanism and work-clamping means having a movement relative to each other at the completion of the stitching on a buttonhole to bring the parts from stitching position to buttonhole-cutting position, a thread-clamping device carried by the work-clamping means and comprising a relatively-fixed member and a relatively-movable member pivotally connected to the fixed member, and means to actuate said relatively-movable member by such relative movement between the stitch-forming mechanism and work-clamping means to clamp the needle thread at the end of the stitching operation.

9. In a buttonhole sewing machine, the combination with stitch-forming mechanism, of Work-clamping means, said stitchforming mechanism and work-clamping means having a movement relative to each other at the completion of the stitching on a buttonhole to bring the parts from stitching position to buttonhole-cutting position, a thread-clamping device carried by the work-clamping means and comprising a relatively-fixed member and a relatively-movable member pivotally connected to the fixed member, and means to actuate said relatively-movable member by such relative movement between the stitch-forming mechanism and work-clamping means to clamp the needle thread at the end of the stitching operation and to release said needle thread as the initial stitches are formed on the next succeeding stitching operation.

In testimony whereof, I have signed my name to this specification.

FRANK ZALESKI.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. O. 

